Application of the Partial Precipitable Water (PPW) Concept in the Determination of a Potential Ice Accretion Index Aloft

This extended abstract intends to further the concept of the use of PPW in meteorological applications. Previous extended abstracts provided insight into the calculation of PPW by adapting an equation from Roland Stull. This equation when combined with the concept of consensus referencing creates an environment whereby water vapor measurements from different upper air measurement systems can be easily compared and adjusted using an independent Integrated Precipitable Water Sensor such as ones based on the GPS sensor or microwave radiometer. This latest approach applies the concept of PPW in a manner that could lead to a new way of assessing the potential amount of ice accretion within various layers of the upper atmosphere. Also included in the technique is the integration of the new ice accretion remark provided by the Automated Surface Observing System (ASOS) which will become operational within the near future and can contribute to the overall amount. Using various weighting functions a user of the technique can quickly assess if significant amounts of precipitable water exist in layers aircraft could be potentially flying through, thus providing a new means for assisting decision makers. The results from the technique can then be converted into an “index” which can vary from no effect to significant regions of potential ice accretion. This approach could provide various communities a wealth of knowledge about the icing potential aloft, based on the concept of PPW, which would be a step forward in future monitoring of the atmosphere.